78105128 has 8 divisors (see below), whose sum is σ = 146447130. Its totient is φ = 39052560.

The previous prime is 78105119. The next prime is 78105163. The reversal of 78105128 is 82150187.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 42797764 + 35307364 = 6542^2 + 5942^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-2 number, since 2×78105128² = 12200822039792768, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 78105094 and 78105103.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4881563 + ... + 4881578.

Almost surely, 2^78105128 is an apocalyptic number.

It is an amenable number.

78105128 is a deficient number, since it is larger than the sum of its proper divisors (68342002).

78105128 is a wasteful number, since it uses less digits than its factorization.

78105128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9763147 (or 9763143 counting only the distinct ones).

The product of its (nonzero) digits is 4480, while the sum is 32.

The square root of 78105128 is about 8837.7105632624. The cubic root of 78105128 is about 427.4577375774.

The spelling of 78105128 in words is "seventy-eight million, one hundred five thousand, one hundred twenty-eight".